The present disclosure relates to light-emitting diodes and, in particular, to a tunable light-emitting diode that is tuned by
Solid-state lighting technology based on light-emitting diodes (LEDs), such as gallium nitride (GaN) LEDs, is becoming mainstream. GaN may be epitaxially grown on various substrates, such as silicon, silicon carbide, sapphire and GaN. GaN LED's typically consist of GaN contact layers sandwiching multiple quantum-well (MQW) structures, such as indium gallium nitride (InGaN) structures. The wavelength of the LED is adjusted by tuning the energy band of the MQW structure, which is accomplished by adjusting the composition, number and thickness of the InGaN wells.
LED devices may be formed by forming the LED structure on a host substrate and performing a spalling process to separate the LED structure from the host substrate. Substrate spalling induces a fracture in a substrate by applying one or more tensile stressed metal layers to the substrate.